Driving mechanism for agitators



Patented Apr. 3, 1923.

ALVAN H. ALBERGEB, OF NEW YORK, N. Y.

DRIVING MECHANISM FOR AGITATORS.

Application filed October 22, 1920. Serial No. 418,788.

To all whom it may concern Be it known that I, ALVAN H. Anisnncnn, a citizen of the United States, residing in the city, county, and fotate of New York, have invented certain new and useful Improvements in Driving Mechanism for Agitators, of which the following is a specification, reference being had to the accompanying drawings, illustrative of one particular embodiment of my invention.

This invention relates to a stirring mech anism or driving mechanism referred to as drives, used for the purpose of driving the shaft of a mixer or apparatus having stirring or mixing blades in a tank or vat either open or closed, or other container in which stirring, mixing, agitating or Similar treatment of materials are effected. It is applicable in particular to such apparatus used for the treatment of chemicals in chemical processes, mixing paints, compounding or otherwise treating of food stuffs or similarly manipulating innumerable other materials.

In particular, the drive is mounted above the container and is peculiarly adapted to support and revolve at the desired speed the shaft projecting downwardly into the material being treated. The embodiment of my invention assures improvement inalignment of the shaft, accessibility and protection of the parts as well as to the operators, economy in operation, durability, prevention of loss of oil or lubricant, and in particular safety against accidental admission of the oil or lubricant for the gears finding its way into the product being treated, while other advantages will be evident from the complete description hereinafter set forth, and from the particular embodiment shown in the accompanying drawings, in which:

Fig. 1 is an elevation showing a tank with the agitator drive mounted on top.

Fig. 2 is avertical section of the drive, on line 2-2 of Fig. 1.

The tank 1 has on its top the drive supporting frame legs 3-3, supporting an alignment bracket 4, having at one side a bearing cap 4 with a grease cup 5.

The gear housing 6 is supported by the bracket legs 33, with its top enclosed by cover plate 7, which in the form shown is made integral with the bracket members 99, and at one side has a small section formed as a removable cover 8 in a position over the place of contact of the gears within the housing, but plate 7 may be made in removable sections. On the underside of the plate 7, a downwardly projecting collar 7 is 'annularly disposed and projects to an extent to prevent oil within the housing from reaching the top of the gear 17 and the agitator shaft 11. Above the gear housing or oil pot 6, a bracket 9 preferably integral with the cover plate 7, bolted at either side by bolts 9, is provided at its apex with a bearing housing 10. This bearing housing is open at the bottom to admit the agitator shaft 11, and is counterbored from the top to admit the bearing case 12 from the top, which in the form shown has two ball races 12, suitably provided for a lateral pressure and for a downward and upward thrust of the agitator shaft 11, the ball cone 13' being secured to the upper end of the agitator shaft 11 and held by washer 13 and a nut 18*. The ball case 12 is held in place by a cap 14 secured by a plurality of bolts, one of which 15, is shown, while a cap 16 covers a central opening through which grease or other lubricant may be readily supplied from above to the bearings.

Within the gear housing a gear 17 is attached to the agitator shaft 11, which passes through the cover 7 I prefer the attachment to be made by a key 18 and -set screws 19-19. The gear 17 has a web 20 conically shaped, so that the worm teeth 21 are located in a plane below the meeting of the web with the hub, while the hub has a downwardly extending portion 22 around which an inner annular wall'23 extends upwardly from the bottom of the housing 6, preventing the oil in the housing from entering, except through control outlet 32.

At one side of the gear housing an excrescence 24 provides with contiguous walls a surrounding housing for the worm 25, supported in bearings in removable caps 26-27 on this extension 22 of the housing.

The worm gear shaft 28 extends from one side through pulleys 29- 50, one of which sump of the housing permits the draining off of all oil and dirt when desired.

It will" thus be seen that the bracket legs 3 are detachably mounted on top of the tank, which may be a vat, pan, or other vessel or container, and these bracket legs support the housing or casing which may be a cast iron integrally-formed part adapted to hold.

oil to any extent desired for the proper lubrication of the gears. While the agitator shaft passes through this tank, it penetrates the cover in a manner which does not permit the loss of oil and it penetrates the bottom within-an annularly-disposed flange or lip projectingupward from the bottom of the housing serving to form a retaining wall for the oil and to prevent the oil from es- .above the lower bearing l, so that a particu larly advantageous support of the agitator shaft .is provided to carry the strain of heavy duty and to prevent vibration and assure continued alignment, and generally most efficient operation under varying and long service.v This bracket may have one or more legs, and if preferred they may be connected or the cover and support may take the form of a. cone detachable from the top of the housing andsupporting the bearing box 10 at. its apex. Thearrangement of gears and the structure of the housing-.as sures the lubricant reaching the gears without the chance of overflow in any objectionableway, irrespective of any particular care in eflecting the supply.

With the top cover 7 of the housing removable, the entire main gear 17 attached to the agitator shaft, may be lifted out of the housing, which, however, would be accomplishedafter detaching thebracket 9 so as to permit the removal of the top bearing and its bearing box 10, F or such disassembling the bearing cap 4 may be first removed, thereby, permitting freer withdrawal of the agitator shaft 11, with, of course, the detachment of the paddles or stirring bars, when vit is desiredto completely detach the agitator shaft.

The lubrication of the main gear 17 is, however.v effected simultaneously with the lubrication of the worm 25 which lies in a lateral excrescence 2% of the housing, therefore providing that the worm and gear run con tinuously in oil under the most advantageous conditions of lubrication.

The worm 25 is, furthermore, so mounted by hearings in the removable caps 1 6 527, so that the worm may be pulled out axially from the housing for inspection, repair and replacement, while the arrangement of the housing with its removable cover permits inspection of the gears with respect to their meshing or adjustment with the greatest facility. lVith the lateral extension of the worm shaft'28, mounted with suitable bearings to support the-fast and idler pulley, power is transmitted from the belt to the fast or tight pulley so as to transmit power to the worm with minimumloss.

The most efficient operation of the gearing, shown as worm drive but likewise the case with the other gearing such as bevel gear and pinion, is made possible in my apparatus in view of the assured proper lubrication, and the required amount of oil is maintained to a maximum depth and regulated by the over-flow outlet 32, so that in all conditions of operation maximum efficiency is maintained. This, however, is accomplished without loss or spreading of oil in any objectionable way, without any packing whatsoever surrounding the gears or their hubs or the agitator shaft. Theelimination of any necessity of packing is accomplished by the construction above described, and in particular the arrangement of the gear withits flange or web so arranged as to permit the reentrant or upturned annular flange of the housing to project well above the maximum limit of the oil bath level in the housing, while still bringing the teeth of the gears into the oil. The entireabsence of the packing on the rotating partseliminates the loss of power which such packing would involve, but at the same time not alone provides more eflicient and power-saving operation, but -with"entire avoidance of undesirable leakage or loss of lubricant, which in some uses of mixing pots or tankswould be absolutely prohibitive or ruinous to the materials'being mixed.

While the bearing supporting lateral strain, provided below the gear and housing, has suitable lining in contact-with the agitator Sllfift,SLlCl1 a bearing maybe-made of material requiring no lubricant, or if lined with Babbitt metal or other metallic lining as preferred, requires a comparatively small amount of lubricant. This bearing, as

shown, is provided with a grease cup 5, and

any'surplus lubricant is either negligible or easily cared for by the operator. Thesuccessful operation of such a 'iparatus is dependent upon the considerable quantity of lubricant or oil necessary for the eificient operation of the gears and thc arrangement and construction embodying my invention primarily safeguard against the loss-of this lubricant and also its possible admixture to the product under treatment in the: appa-- ratus.

For different purposes, such agitator:

and the consistency of the material stirred or kneaded may involve light or heavy power for the turning of the mixing bars or paddles, While high power and slow speed are most effectively provided by the worm drive, higher speeds may be obtained in apparatus in some cases more advantageously by bevel gear and pinion or other gearing, but-in all such the features of my invention may be embodied and effect the same advantages as have been herein set forth.

With an open top tank the entire agitator shaft and drive mechanism may be readly removed by the unbolting of the frame, and the agitator shaft may be removed in any case with the gear mounted in position avoiding the necessity of readjustment when again assembling. With the arrangement of the bearings no thrust, either upward or downward, is taken on the gear hub or on collars, but the axial thrust of the stirrer shaft is most effectively carried by bearings remote from the'point of entry of the" shaft into the tank, and the thrust bearing is so provided that its lubrication may be given perfect attention with simplicity, and its inspection readily effected, while at the same time a heavy felt washer or like packing below the bearing prevents the chance escape of the small amount of lubricant preferably such as grease or Vaseline necessary for the ball bearings. Furthermore, the ball bearing box is so located that any accidental leakage will be readily observed on the agitator shaft before it could reach the tank, but the intermediate position of the gear with the centrifugal force affecting any oil which might reach the hub of the gear, provides an additional safeguard to divert any chance escape of lubricant into the main housing reservoir, and therefore in practice entirely eliminates the chance of lubricant from the ball bearings ever reaching the tank.

On the whole, the structure provides a compact unit in which the greatest efficiency can be provided for the operation of mechanical parts, safety, simplicity, of construction, durability and reliability of operation are assured, while the main factor economy of operation is a net result which in practice means an apparatus of greatest value.

While various modifications may be made without departing from the spirit of my invention, what I claim and desire to secure by Letters Patent is: A 1. A mixing or stirring apparatus comprising a tank with stirrer shaft and blades, a bracket detachably supported on the top of the tank and carryin a gear casing comprising a seamless annu ar housing with integral bottom and up-turned outer and inner walls, a detachable cover for said housing detachably secured in contact with the rim of the outer up-turned wall of the housing and having a central opening free of contact with the stirrer shaft, a stirrer shaft bearing below and separate from the bottom of the housing and a bracket supporting said bearing in fixed relation to the housing, a

thrust bearing above the housing remote from a drive gear attached to the stirrer shaft and rotating in the housing.

2. A mixing or stirring apparatus comprising a tank with stirrer shaft and blades, a bracket detachably supported on the top of the tank and carrying an annular housing, an integral bottom and a detachable top cover for said housing, openings permitting the free passage of the stirrer shaft through the housing and through the cover, a bearing below and out of contact with the bottom of the housing supported by the bracket, a second detachable bracket above the housing and means supported by said bracket to carry a remote bearing, a drive gear attachedto the stirrer shaft above the lower bearing and having its periphery enclosed by and rotating within the housing and dipping into the level of the oil bath within said annular housing.

3. Drive mechanism for an agitator or mixer shaft, comprising a supporting bracket and combined gear and oil housing, gears within said housing, an oil-retaining wall between the drive gear and the agitator shaft and an oil-clear opening for the agitator shaft surrounded by the oil-retaining wall, a superposed removable supporting member, a remote thrust bearing above and out of contact with the bottom of the housing and an aligning bearing below the housing.

4. Driving mechanism for a vertical stirrer or agitator shaft, including a drive gear detachably secured to the shaft, a complementary gear on one side thereof, a housing enclosing the gears and having an annular wall extendingupwardly from the bottom adapted to confine the oil to the outer annular portion of the housing and permit free passage of the agitator shaft through the bottom, an oil-level control outlet below the top level of the central wall and a top thrust bearing and a lateral bearing supported rigidly with respect to the housing whereby the stirrer shaft passing through the housing is carried out of contact with the walls of the housing.

5. A stirrer drive mechanism comprising I the stirrer shaft, the gear attached thereto, a conical web on said gear and a tooth periphery supported in a plane below the juncture of the web with the hub engaged in said gear, a housing enclosing the tooth periphery of the gear and engaging gear, said housing having a reentrant wall on its bottom rising around the hub of the gear above the level of the contact plane of the teeth, one or more supports for said housing and cooperating means to support a bearing for the stirrer shaft below the housing,la detachable structure above the housing and a detachable thrust bearing supported therein wherebythe stirrer shaft is carried by said bearings out of contact with the housing and the gear teeth enclosed within and adapted to run-in oil confined Within the housing.

6. A stirrer drive mechanism comprising the stirrer shaft, a gear attachedthereto, an

oifsetvvebon said gear and a toothed periphery supported in a' plane below the" posed about the stirrer shaft carryingsaid v housingand supporting a bearing adapted to resist lateral strain on said stirrer shaft, a detachable structure above the housing cooperating with a cover therefor, and a thrust bearingsupported in said structure, whereby said stirrer shaft is carried by bearings out of contact with the :housing, and with the gear teeth running in oil confined within saidhousing.

7. A stirrer or mixer drive adapted to be detachably mounted on a tank or the like, comprisingan integral gearhousing and supporting leg or legs, an agitatorshaft passing through the housing and an alignment bearing supportedby said'leg or legs, a supporting member on the top of the housing carrying a thrust bearing at its apex supportingthe upper end of the agitator shaft, a detachable cover for the housing,bottom walls in said housing confining an oil bath about the main gear teeth and a flange eX tending above the level of the oil bath the main gear being detacha-bly secured to the agitator shaft.

8. A stirrer or mixer drive comprising a shaft, a gear attached thereto some distance from the upper end of the shaft, thrust bearings atthe upper end of the shaft and a bearing adapted to resist lateral strain inproximity to the plane of the gear, a housing surrounding but out of contact with said shaft and an annular chamber in said housing supporting oil within the path of the gear teeth and" a detachable cover for said housing with an eX- tended support carrying said remote thrust bearing, a bracket supporting said housing and means to attach and detach said bracket from a vat, tank or like vessel.

9; Drivingwmechanism for a vertical stirrer OPflgltZitOI' shaft,-including a drive gear detachably' secured to the shaft, acomplementary gear therefor, a housing enclosing. the gears and having an annular wall extending upwardly from the bottom adapted to confine'oil insaid housing to an annular portion radially outward from confrmnghousmg enclosing the gears, a,

central passage for the agitator shaft through the bottom of the housing sur- 1 rounded by an lip-turned annular wall in tegral with the seamless housing, a top bearing supported remote from the housing and out of contact therewith and a lateralbearing supported rigidly with respect to and below the bottom of the housing.

11 Driving mechanism for a vertical stirrer or agitator shaft, including a drive gear detachably secured to the shaft, a complementary gear associated" therewith, a housing'enclosing the'gears and havingan integral-bottom with a-central aperture, an oil level over-flow control. attached to said housing, an elevated annular rim around said aperture extending-upward from the bottom, and integral with the bottom to a level above the level of the oil over-flow, a detachable top cover for the housing, a top thrust bearing above the cover and separated therefrom, and means for holding it in rigid alignment with the housing, a bottom bearing for. the agitator shaft below the level of the raised-annular portion of the housing bottom,surroundingthe opening in the bottom and means for rigidly holding saidbearingwith relation to the bottom.

In testimony whereof, Ihave signed my name to this application, in the presence of two subscribing witnesses, this 15th day of October, 1920.

' ALVAN H. ALBERGER. lVitnesses O. H. ARMSTRONG, J. G. SMITH. 

